1.Satellite ranging configuration profile

1.1Standards

  1. CCSDS recommendation only covers the PN ranging (BB: 414.1B-1)
  2. ECSS-E-50-02 addresses the ESA Code ranging (made of tones + codes)
  3. Tone Ranging: ESA-like tone Standard, Inmarsat tone Standard, continuous tone Standard

1.2Characteristics

The table below summarize the main characteristic of the three types: PN, Hybrid (Tone & code) and Tone. Tone ranging is mentioned for completeness but will not be considered (no standard)

Parameters / PN Ranging / Hybrid (ESA Code) / Tone Ranging
Ranging mode / Transparent, Regenerative / Transparent / Transparent
Modulation / PM on carrier, Square wave / PM on carrier, Sine Wave / PM on carrier, Sine Wave
Ranging Tx Mod Index / 0.1 to 1.4 rad peak / 0.1 to 1.4 rad peak / ?
Ranging Rx Mod Index / 0.1 to 1.4 rad peak / 0.1 to 0.7 rad peak / ?
Chips rate / Tone Freq. / Per table B-1 (414.1 B-1)
Described by coefficients “l” and “k” / 100 kHz to 1.5 Mhz / 1 Major + 1 to 6 Minors
Code Type (PN) / T2B (Transparent/Regenerative)
T4B (regenerative only) / n.a. / n.a.
Code Lenght (Hybrid) / n.a. / 0 to 20 / n.a.

1.3Ranging configuration parameters

The Ranging configuration parameters are listed below:

Parameters / Type and Values / Comments
General
Ranging Mode / Enum: Transparent, Regenerative / Is this relevant for GS configuration?
Data measurements Parameters
Duration of measurement / Integer: 10 to 1 000 000 s (1s step)
Sampling Period / Integer: 1 to 120 s (1s step)
Max sample per data set / Integer: 10 to 10 000 (1 sample step)
Dataset Kind / 2 characters / Probably not needed
Configuration Parameters
Ranging Type / Enum: PN, Hybrid, Tone / Tone ranging not considered?
Tone Frequency / Float: 100 kHz – 1.5 MHz (1 mHz step) / Only applicable to Hybrid Ranging
Chip rate(l/k) / 2xIntegers / Only applicable to PN Ranging
As per table B-1(414.1 B-1) the chip rate is expressed in term of coefficients “l” and “k” with:
- “l” from 1 to 64
- “k” = 6, 8, 9 or 10
The Actual chip rate can be calculated from these 2 coefficients and the UL band used.
Code type / Enum: T2B-Sine, T2B-Square, T4B-sine, T4B-Square / Only applicable to PN Ranging
Transmitted Tone/PN-code Mod index / Float: 0.1 to 1.4 Rad Peak (1 mrad step) / Applicable to PN and Hybrid ranging
Expected Rx Tone/PN-code Mod index / Float: 0.1 to 1.4 Rad Peak (1 mrad step) / Applicable to PN and Hybrid ranging
Tone/PN-Chip open-loop integration Time(see note 2) / Float: 1 to 1000 s (0.1 s step) / Applicable to PN and Hybrid ranging
Tone/PN-Chip open-loop settling Time(see note 2) / Float: 1 to 1000 s (0.1 s step) / Applicable to PN and Hybrid ranging
Code modulation Index Scheme / Enum: High&Low, Low, High
  • High&Low = 45deg during ambiguity resolution, 27.5 deg after
  • Low = always 27.5 deg
  • High = always 45 deg
/ Only applicable to Hybrid Ranging
Maximum Code Length / Integer: 0 to 20 / Only applicable to Hybrid Ranging
Code integration Time(see note 2) / Float: 0.5 to 10 000 s (0.1 s step) / Only applicable to Hybrid Ranging
Code sequence immediate restart / Enum: Yes, No
If Yes, sequence will be automatically restarted after incorrect correlation of two successive codes / Only applicable to Hybrid Ranging
Repetitive code sequence / Enum: Yes, No
If Yes, the complete sequence will be repetitively transmitted / Only applicable to Hybrid Ranging
T4B code: Expected on-board acq duration(see note 3) / Float: 1 to 98 s (0.1 s step) / Only applicable to PN Ranging
T2B code: Expected on-board acq duration(see note 3) / Float: 1 to 6 s (0.1 s step) / Only applicable to PN Ranging
Other Parameters
Expected Propagation Delay / Integer: 0 to 2 000 000 s (0.01 s step) / Or can use the trajectory prediction?
Expected Propagation delay derivation / Float -1E-3 to 1E-3 (1E-9 step)
Time of given EPD / Time
Dual Ranging / Enum: Yes, No / Do we want such service?

Notes:

  1. In the MD list, monitored data are split into Uplink ranging and Downlink ranging. Do we want to keep the same approach?
  2. For Hybrid ranging the Tone Integration time, Tone settling time and code integration time can be derived from the expected Rng S/N0 these parameters might be replaced by the expected Rng S/N0 value?
  3. In the same way, the on board acquisition time for the T2B and T4B code can be derived from the ranging P/N0 (see 414.1 B-1)
  4. The expected propagation delay can also be derived from the Trajectory prediction.
  5. Dual Ranging. Any interest for cross support?